Incidence and risk factors of preparation errors in a centralized cytotoxic preparation unit

A major objective of centralized preparation is to improve the quality of the final product, and thus their safety for the patient. Few data are available concerning errors occurring during preparation and the risk factors associated with the errors. To assess risk factors associated with preparation errors in a centralized cytotoxic preparation unit.

Medication errors were detected during preparation (self-education by technicians) or at the time of control (qualitative and semi-quantitative). For each preparation, several potential risk factors were studied. Univariate analysis was carried out using Chi-2 or Fisher exact tests. Variables with p < 0.15 associated in univariate analysis were entered in a stepwise regression model. In an overall analysis, all types of error were considered. In a second analysis, only major errors (errors associated with drug, dose or major incompatibility) were studied.

Analysis included 30,819 preparations. Overall and major error rates were respectively 0.45% and 0.19%. The number of bottles (more than one), the volume of active solution (more than 50 ml) and the daily workload were the major risk factors identified by successive univariate and multivariate analysis.

Low rates of medication errors compared to previous studies were reported. Major preparation errors were principally related to drug labeling (dose/bottle and concentration) and workload. Preparation mistakes appeared to have many causes. These results could be used to revise the general organization and determine a suitable purchasing policy.